The pros and cons of having just one staircase in high rise residential buildings was the subject of an impassioned debate on Tuesday 17 May at the 7th International Tall Buildings Conference, held alongside FIREX International in London. Here, we report on the key points raised by the panellists.
The panel discussion came against the backdrop of developers of two high-rise schemes in London – respectively 51 storeys and 35 storeys high, the latter of which will be just 400m from the site of Grenfell Tower – being forced to reconsider their plans for a single staircase in their buildings.
Peter Wise, originally an operational firefighter and now a chartered engineer and Technical Director of Part B Consulting, saw both sides of the argument and remains ‘agnostic’ as far as single stairs in new builds are concerned. The important point, he said, is the design process and the profile of the building users, as well as the role of the fire and rescue service. A single stair is dependent on a stay put policy in the event of fire. “As an engineer, I hope we can still have single stairs; as a former firefighter, I am more sceptical.”
But a stay put policy does not mean rigid adherence to this – even early fire service operational guidance said fire services should be prepared to evacuate buildings. “We have to ask ourselves whether human behaviour has changed after Grenfell – these are areas that need to be worked on.”
Looking ahead and bringing in the safety case regime for high rise residential buildings, the question would be how well the Building Safety Regulator will work with building managers to keep buildings safe. “We have to make sure that regulators are checking that things are being done properly,” said Wise.
Jane Duncan OBE, an Architect and Chair of the RIBA Expert Advisory Group on Fire Safety, said the debate on single stairs should ultimately be examined from the point of view of the residents being safe. “Grenfell demonstrated that we can’t guarantee that every building is properly built and maintained, and it’s difficult to make a building perfect. Can you rely on a very tall building with a single stair?
We need to be designing buildings for the future and not for just tomorrow. We need to ask: if everything goes wrong, how do we get people out?” She added: “If I’m in a high-rise and there’s a fire, I’m going to ignore any ‘stay put’ advice.”
Paul Bussey, Senior Technical Consultant at AHMM architects, said only South Korea and the UK allow single staircases in buildings regardless of height. The argument was about an “appropriate” means of escape, as described in Approved Document B. But this approach failed at Lakanal House and at Grenfell Tower, while fire engineered solutions tend to “game” the system. “I’ve spent 30 years designing out staircases, but since Grenfell I have considered, why? It’s also very difficult to get builders to build what is designed with design-build contracts.”
Shula Rich is Vice-Chair of the Federation of Private Residents’ Associations and advises leaseholders and managing agents on right-to-manage and block management issues. She said residents feel so much safer with two staircases and feel lucky to have them. The key issue is about the distance to a staircase, but with new builds it’s all about cost.
Simon Lay, co-founder of OFR Consultants and a fire engineering specialist, agreed that we need appropriate means of escape and firefighting access, properly built and maintained. But if a building is designed or built badly, even two staircases may not help. “Is it just to make people feel safer? If you wrap a building with combustible cladding, then what? Just look at legacy two-stair buildings that don’t have proper compartmentation or sprinklers.”
He added that two-stair buildings allow for much longer travel distances without smoke ventilation.
“Thanks to the cladding crisis, people now feel unsafe. But residents should be able to put fire safety at the back of their minds, so we need to persuade people that buildings can be safe with a single staircase.”
The debate over tall buildings requiring single or dual staircases has been ongoing for some time in the fire sector.
As a prime example, the construction of a new skyscraper in London's Canary Wharf was halted in 2021 over fire safety concerns centred around the design "not providing suitable and convenient means of escape and [an] associated evacuation strategy for all building users."
The brigade also highlighted that, in properties with a single staircase, a developer would be expected to demonstrate “resilience” of a building in the event of a fire, which had not been done in this case.
In a statement, Tower Hamlets Justice for Leaseholders, says that it considered the move to be a “sign of the start of a new era in fire safety.”
Secretary of the Tall Building Fire Safety Network, Russ Timpson, who manages and runs the Tall Building Fire Safety Conference, added at the time: “In my opinion, you have to build resilience.
“You have to have a plan A and a plan B because if stay put doesn’t work, a simultaneous evacuation is an almost impossible challenge with a single staircase. Around the world, firefighters talk about having one escape stair and one attack stair.”